Trophic species

A trophic species is a group of species that are aggregated according to their common trophic (feeding) positions in a food web or food chain. Trophic species have identical prey and a shared set of predators in the food web. This means that members of a trophic species share many of the same kinds of ecological functions. The trophic species concept is similar to the concept of an ecological guild, but the latter focuses on how resources are used through common adaptations to similar problems. The concept was first devised by Joel Cohen and Frederick Briand in 1984 to redefine assessment of the ratio of predators to prey within a food web. The category may include species of plant, animal, a combination of plant and animal, and biological stages of an organism. The reassessment "lumped" similar species according to habit rather than genetics and gave the result that the ratio of predator to prey in food webs is generally 1:1.